God rays, volumetric light, visor reflections / water drops, lens flares, depth of field, night & thermal vision scopes, dynamic wet surfaces with reflections, rainbows and many other effects. BETA UPCOMING!
I just had the funny idea of trying to apply the sun shafts effect to specific artificial light sources in indoor/underground levels as well.
The concept how to do this is in my mind, however I cannot say yet whether it is really doable the way I think.
So for the moment it's basically just concept stage.